Bristol Jupiter VIIIF Radial Engine

The Jupiter was Great Britain’s most successful high-power, air-cooled engine in the 1920s and ’30s. Bristol Aeroplane acquired the assets of Cosmos Engineering in 1920, which included the Jupiter and its designer, Roy Fedden. The Royal Air Force adopted the Jupiter as its first post–World War I engine in 1923. Bristol and its licensees built more than 7,000 Jupiters for at least 262 different aircraft types.

The Model VIII was the first Jupiter to use reduction gearing, which allowed the engine and propeller to rotate at different speeds for increased efficiency. The Model VIIIF powered the Blackburn B.T. 1 Beagle, Boulton-Paul P.29 Sidestrand III, Handley Page H.P.33 Clive I, Vickers 192 Vildebeest, and Westland Wapiti I, IA, II, and IIA. The “F” denoted a lightweight forged aluminum cylinder head, an important advance in reciprocating engines.

The Jupiter was Great Britain’s most successful high-power, air-cooled engine in the 1920s and ’30s. Bristol Aeroplane acquired the assets of Cosmos Engineering in 1920, which included the Jupiter and its designer, Roy Fedden. The Royal Air Force adopted the Jupiter as its first post–World War I engine in 1923. Bristol and its licensees built more than 7,000 Jupiters for at least 262 different aircraft types.

The Model VIII was the first Jupiter to use reduction gearing, which allowed the engine and propeller to rotate at different speeds for increased efficiency. The Model VIIIF powered the Blackburn B.T. 1 Beagle, Boulton-Paul P.29 Sidestrand III, Handley Page H.P.33 Clive I, Vickers 192 Vildebeest, and Westland Wapiti I, IA, II, and IIA. The “F” denoted a lightweight forged aluminum cylinder head, an important advance in reciprocating engines.